Dispatching errors across iframes don't match webplatform tests

third_party/WebKit/Source/bindings/core/v8/ScriptState.h

Index: third_party/WebKit/Source/bindings/core/v8/ScriptState.h
diff --git a/third_party/WebKit/Source/bindings/core/v8/ScriptState.h b/third_party/WebKit/Source/bindings/core/v8/ScriptState.h
index b0b0fd8530be5f9b3711f8272a63d42d98737c63..f17e013cbaf08e0f7655bd9434ce25eddc46dd0b 100644
--- a/third_party/WebKit/Source/bindings/core/v8/ScriptState.h
+++ b/third_party/WebKit/Source/bindings/core/v8/ScriptState.h
@@ -183,6 +183,40 @@ class ScriptStateProtectingContext {
   ScopedPersistent<v8::Context> m_context;
 };
 
+class ScriptStateForErrorEvent {
+  STACK_ALLOCATED();
+  WTF_MAKE_NONCOPYABLE(ScriptStateForErrorEvent);
+
+ public:
+  static ScriptStateForErrorEvent* current() { return s_topOfStack; }
+
+  ScriptStateForErrorEvent(v8::Local<v8::Context> context)

[haraken, 2016/11/02 01:40:18]

Add explicit.

+      : m_prev(s_topOfStack),
+        m_isolate(context->GetIsolate()),
+        m_context(m_isolate, context) {
+    s_topOfStack = this;
+  }
+
+  ~ScriptStateForErrorEvent() {
+    s_topOfStack = s_topOfStack->m_prev;
+  }
+
+  ScriptState* scriptState() {
+    return ScriptState::from(m_context.newLocal(m_isolate));
+  }
+
+  v8::Local<v8::Context> context() const {
+    return m_context.newLocal(m_isolate);
+  }
+
+ private:
+  static ScriptStateForErrorEvent* s_topOfStack;
+  ScriptStateForErrorEvent* m_prev;
+
+  v8::Isolate* m_isolate;
+  ScopedPersistent<v8::Context> m_context;

[haraken, 2016/11/02 01:40:18]

You can use v8::Local<v8::Context> because ScriptStateForErrorEvent is used only
on the stack.

However, I'd prefer just storing RefPtr<ScriptState>. Then you don't need to
store v8::Isolate* since you can get it via m_scriptState->isolate().

+};
+
 }  // namespace blink
 
 #endif  // ScriptState_h